You know what? at this point no one knows.. well besides Greg Berlanti and Team Flash. This villainous character in The Flash TV show is soo awesome that people don't even care about The Flash. The man under the mask is something we might not get to know until episode 20 or 21 or even 22 but what we surely do know is that... A) he can F***ing catch lightning
B) he is faster than The Flash
and C) he surely is a Badass
The directive team is doing such a great job at the plot twists and the minute details and.....at keeping Zoom's identity a secret until the huge Climax of the show, the same way that they did in season 1 with Reverse Flash (Eubard Thawne).